The　air　source　heat　pump　(ASHP)　systems　assisted　by　solar　energy　have　drawn　great　attentions,　owing　to　their　great　feasibility　in　buildings　for　space　heating/cooling　and　hot　water　purposes.　However,　there　are　a　variety　of　configurations,　parameters　and　performance　criteria　of　solar　assisted　ASHP　systems,　leading　to　a　major　inconsistency　that　increase　the　degree　of　complexity　to　compare　and　implement　different　systems.　A　comparative　literature　review　is　lacking,　with　the　aim　to　evaluate　the　performance　of　various　ASHP　systems　from　three　main　solar　sources,　such　as　solar　thermal　(ST),　photovoltaic　(PV)　and　hybrid　photovoltaic/thermal　(PV/T).　This　paper　thus　conducts　a　systematic　review　of　the　prevailing　solar　assisted　ASHP　systems,　including　their　boundary　conditions,　system　configurations,　performance　indicators,　research　methodologies　and　system　performance.　The　comparison　result　indicates　that　PV-ASHP　system　has　the　best　techno-economic　performance,　which　performs　best　in　average　with　coefficient　of　performance　(COP)　of　around　3.75,　but　with　moderate　cost　and　payback　time.　While　ST-ASHP　and　PV/T-ASHP　systems　have　lower　performance　with　mean　COP　of　2.90　and　3.03,　respectively.　Moreover,　PV/T-ASHP　system　has　the　highest　cost　and　longest　payback　time,　while　ST-ASHP　has　the　lowest　ones.　Future　research　are　discussed　from　aspects　of　methodologies,　system　optimization　and　standard　evaluation.　(C)　2019　Elsevier　Ltd.　All　rights　reserved.